FALL PREVENTING LADDER AND RECEIVING FRAME OF UNDERGROUND STRUCTURE COVER HAVING FALL PREVENTING LADDER

摘要

PROBLEM TO BE SOLVED: To provide a fall preventing ladder, and a receiving frame of an underground structure cover having the fall preventing ladder for allowing the fall preventing ladder to maintain a falling-down state even if a cover body is opened by uplift pressure.;SOLUTION: This invention is constituted so that a lock member 23 is arranged on the base end side of a ladder body 11, and the ladder body 11 slides to the tip side against a case of always pressing a base part 9 by energizing force of a coil spring 27 in this lock member 23, and the tip of the ladder body 11 supported by a support part 6 of the receiving frame 2 can engage with an upper wall 7 above the support part.;COPYRIGHT: (C)2005,JPO&NCIPI